Process and apparatus for sizing yarns



June 25, 1946. J. A. CLARK PROCESS AND APPARATUS FOR SIZING YARNS Filed Nov. 17, 194:5

IN V EN TOR.

k m m P m\ mN m M w HM H m A A .IP H S IIHH LH I m M k E Y B Patented June 25, 1946 PROCESS AND APPARATUS ma srzmo YARNS James Andrew Elm-k, White Plains, N. Y., as-

signor to sylvania Industrial Qorporation, Frederickshurg, Va, a corporation oi Virginia Application November 17, 1943, Serial No. 510,608

3 Claims. I

The invention relates in general to a process and apparatus for sizing warp yarns and to correlated improvements designed to enhance the properties of the warp yarns in weaving.

It is known to size warp yarns, prior to weaving, with an aqueous solution of water-soluble colloids, such as starch, gum, dextrine, gelatine, in order to facilitate the weaving of such yarns. In the prior practice, however, the us of these water-rsoluble substances for sizing the war yarns has been attended by certain disadvantages. The process has been slow and hence expensive because of the high viscosity, slow penetration and low drying ratio of the solutions used. Moreover, yarns sized with water-soluble colloids show a pronoimced decrease in stiffness after the first laundering; must be de-sized prior to dyeing, mercerizing or bleaching, which in itself decreases the yarn resistance; and have in any case a low resistance to abrasion, which causes the nap to be raised during weaving. It is also necessary to carry out the weaving of such prior yams in an atmosphere of relatively high humidity, which tends to corrode the metal parts of the loom.

To obviate those diillculties and disadvantages,

it is now proposed to size the warp yarns prior to weaving with an alkali-soluble water-insoluble cellulosic colloid. This novel size presents many advantages over the use or water-soluble substances heretofore used, in fact its use obviates all the diiiiculties mentioned above, but alkali-soluble water-insoluble cellulosic colloids possess the P -Petty of being inherently tacky, causing the yarns to adhere to each other during the sizing operation, and this raise a new difliculty which it is the object of the present invention to overcome.

It is the general object of the present invention to provide a process and apparatus for slashing warp yarns in a rapid and economical manner.

It is a specific object o! the invention to provide a process for permanently sizing a multi plicity of warp yarns in a continuous manner.

It is another specific object or the invention to provide an apparatus for slashing warp yarns which is adapted to be used for sizing the yarns with a tacky size. 1

Other objects of the invention will in part be obvious and will in part appear hereinafter.

According to the present invention, there is provided a process of sizing a multiplicity of warp yarns with a tacky composition prior to weaving while avoiding the adhesion of adjacent yarns to each other. More particularly, the invention relates to a process for collectively sizing a multiplicity of warp yarns while arranged in the form 2 of a weftless web with an alkaline dispersion of an alkali-soluble water-insoluble cellulosic 001- loid, separately coagulating said colloid on the individual warp yarns, whereby the nap on the yarns is permanently laid and the twist stabilized, and drying the yarns.

The apparatus of the invention comprises, in

combination, means to treat warp yarns in the form of a weftless web, with a. liquid sizing composition, in particular an aqueous dispersion of a water-insoluble coagulable colloid, means to separate the yarns, means for coagulating the colloid on the yarns while so separated, and means for drying the yams. The apparatus preferably includes means for separating the yarns before and after coagulating the colloid thereon whereby the yarns do not adhere to each other in passing through the subsequent treating devices.

The invention accordingly comprises a process having the steps and the relation of steps one to another, and an apparatus having the elements lulose derivatives and synthetic resins, or mixtures of these fibres, and whether carded or combed, or made of continuous filaments or staple fibres.

The process and apparatus of the present invention may be used with any warp sizing composition but in particular with tacky compositions such, for example, as an aqueous dispersion, preferably an alkaline dispersion of alkali-soluble water-insoluble cellulosic colloid. For the cellulosic colloid there may be employed the alkalisoluble water-insoluble cellulosic others as a class. such for example as alkyl-cellulose ether, hydroxy-alkyl cellulose ether, carboxy-alkyl cellulose ether, and. the like; also, the alkali-soluble water-insoluble cellulose materials per so as a class, such, for example, as cellulose dissolved in any of its known solvents, such a an alkali solu tion of 5% to 10% concentration, alkaline solutions of zincates, and stannates, or strong organic bases such as aralkyl ammonium hydroxides; also ent No. creates, and in British Patent No.

, j of the apparatus of the invention for 507,138; also starch,rosin, resin, rubber latex and other sizes may be used.

Among the cellulose ether solutions, there 18 preferred an alkali-soluble water-insoluble hydroxy-ethyl cellulose ether dissolved in an aqueous alkali solution,- and among the cellulosic solutions, there is preferred a degraded cellulose dissolved in an aqueous alkaline zincate solution as, disclosed in U. S. Patent No. 2,289,085.

The cellulosic colloid may be coagulated from its alkaline dispersion by means of any of the 1 known coagulants for viscose, such,for example, I, as acids, acid salts, salts and heat, also by the action of hot water. I

The alkaline dispersion of the cellulose colloid is preferably applied to the yarn while the dispersion has a low viscosity. It is characteristic -of the degraded cellulose solutions above dis closed that their alkaline dispersions have very low viscosities. However, alkali solutions of the cellulose ethers may be made of low viscosity either (a) by degrading the cellulose ether before or after its manufacture by the use of heat alone or by heating'with acids, alkalies, or oxidizing agents; or (b) the viscosity of the alkaline solutions' may be lowered by adding to the. solution an oxidizing agent; or by heating the aqueous alkaline solution of the cellulose ether during applicationto the yarn to a temperature at which it shows a pronounceddrop in viscosity such, for

example, as a temperature between 140 and The cellulosic content of the alkaline dispersion may be varied over a wide range, but usually if the dispersion contains from 3% to 8%, preferablyabout 6% by weight'of the solution of the cellulosic colloid, a satisfactory warp sizing will be obtained. The quantity of alkali, which is normally a strong alkali such as sodium hydroxide, potassium hydroxide or aralkyl-ammonium hydroxide, may be varied according to the amount requiredto completely and uniformly disperse the cellulosic colloid, which amount is usually between 5% and 10% by weight of the solution.

water-insoluble colloid serves to permanently bind the pigments ordyestuffs'to the yarns.

For a. more complete understanding of the nature and objects of the present invention, reference should be had to the accompanying drawin: in which thereis illustrated one embodiment permanently sizing warp yarns. v

Fig. 1 is a dical representation in side elevation of one embodiment of the yarn sizing apparatus or the invention;

4. sizing composition held in four-box slasher. The box. I2 is provided with a jacket l3 and, ill the space so provided, hot water is introduced through the pipe I4 and withdrawn through the pipe ii. The remaining boxes l8, I1 and ll of the slasher are substantially identical in construction, and each is provided with a submerged roller l9, and a pair of pressure rollers 20 positioned above each box respectively, so that the excess liquid carried by the yarns is caused to flow back into-the respective box. The pressure rollers 2| and 22 at the exit of the box l2 are of s ecial construction. It has been found that to avoid flattening the yarns and to produce an even distribution of the size thereon, one or both of the rollers 2| and 22 is provided with a very rough surface, for example, by wrapping the roller with a very rough fabric such, for example, as burlap. The top roller 2! will normally bethe wrapped roller and the bottom roller 22 will be 'a roller provided with a soft resilient surface such as rubber. The rollers are provided with a means (not shown) for subjecting the yarn to substantial pressure as it passes between the rollers.

From the nip of the rollers 2| and 22, the sized warp yarns III are separated by a leash or splitter rod 23', and the size, e. g. a cellulosic colloid, coagulated as the yarn passes through a liquid coagulant contained in box It. After coagulation the yarns are again separated by a leash or splitter rod 23.. The yarns are washed, e. g. with hot water .contained in box l1 and may be subjected to a second washing e. g. with dilute alkali in the box l8. After this treatment, the sized yarns are dried by suitable means as by passing them over and under the heated drying cans 24 and 25, and the dried yarns are then wound upon the beam 2-8, which may be a split beam. To prevent overlapping of the yarns-one upon the other, there may be provided, at suitable points in the course of travel, combs or reeds 21 of conventional design, such reeds being shown in the figure at points where the yarns leave the box H, the box l8, and before and after they pass "over the drying cans. I

'It is important and highly desirable that the warp yarns be separated, asby passing alternate yarns over and under the leash or splitter rods 28 and 23'. before and after coagulation of the size, e. g. the cellulosic colloid, since the coagulation of the size while the yarns are in contact tends to cause adjacent yarns to adhere to each other. i

By way or illustrating, but not by way or limit-- ing the invention, there will be given the following example:

Combed or carded cotton warp yarns, intended for use in twills or drills for military uniforms, are sized by passing the yarns through a sizing 00 composition comprising 6% alkali-soluble water- Fig. 2 is a longitudinal view, partly in section. I

or one of the yarniseparatingrollers utilized in the apparatus shown in s, and

Fig. 3 is a, diagrammatical representation in side elevation of a second embodiment of the yarn sizing apparatus of the invention.

Referring to Fig. 1, the warp yarns I0 are unwound from the'beam H and passed into the insoluble cellulose ether (initial viscosity of 2 7 compared to glycerin), 8% sodium hydroxide, and the remainder-water. To this solution is added 0.2% of ammonium persuliate which reduces the relative viscosity of the composition by oxidation to between 0.5 and 0.1. The sizing composition is placed in the box I! or the apparatus shown in the drawing and the composition heated to, a temperahire'ot F.. The warp yarns are passed successively through the hot composition contained in box l2, then through the pressurerollers 2| and 22, separated bytl'ie leash rod 28, and then pissed into thebox" containing a 6% aqueous solution oisulphuric acid as coagulant. The excess-coagulant]:

the first box, 12 of a asoacss squeezed out by means of the pressure rollers 2|, the yarn separated by the rod 18, and then washed in water contained in the box I? heated to 140 F. Finally. the yarns are subjected in the box ll to washing with an aqueous solution of 5% ammania, and the washedyarns are then dried on the cans 24 and 2!.

In Fig. 3 there is shown a second embodiment of the apparatus of the invention, in which the multiplicity of the yarns ID are unwound from the beam II and passed over tension rolls 8 and 9. and then into a slasher'having boxes i2, it, I! and II similar to those of the apparatus shown in Fig. 1. Likewise, the pressure rollers 2i and 22 at the exit of box I: have the same surface as the rollers 2| and 22 in the apparatus of Fig. 1. The apparatus shown in Fig. 3 differs from that shown in Fig. 1 in that the yarn separating means are rotatable rollers. Such meansare provided for saturating the yarns with the oellulosic colloid while the yarns are separated from each other at least over a part of their path through the bath. For example, by providing in the box I! two submerged rotatable rollers i and 2, alternate yarns pass under the roller I and the other yarns pass under roller 2, all the yarns passing through the nip of the rolls II and 22 as in the apparatus of Fig. 1. Further, in Fig. 3, the sized yarns in are maintained in a separated condition during coagulation by passing alternate yarns under the submerged roller 3 of box it and the intervening yarns first over a roller 4 and then under a submerged roller 5, all the yarns passing under a common roller 30 and through the nip of the rollers 20. Thus, adjacent yarns are not in contact and are separated as they pass into the coagulant contained in the box ii. The yarns pass from the box IE into the box I! where they are washed. It has been found that if the yarns are separated during coagulation of the size, it is not essential that they be separated during. washing, although box i1 may likewise be provided with separating rolls as in the box ii of Fig. l or splitter rods like the rods 28 shown above in box I! in Fig. 1. After washing in box H, the yarns are subjected to a second washing in the box is. Sprays 29 of washing fluid may be positioned to wash the yarns as they pass between the rollers 20. Thereafter the yarns are dried in a suitable manner, for example by the means shown in the apparatus of Mg. 1.

It has been found that to facilitate the proper feeding of the yarns through the nip 0! the rolls Ii, 22 and the squeeze rolls 20, it is advisable to align the yarns just before they contact these rolls. This may be done. for example, by positioning grooved rollers 31 above each bath and adjacent the rolls 22 and 2| so that the individual yarns I! are caused to pass into the grooves 32 of the roller II before the yarns contact the rolls 22 and 20. A suitable grooved roller is shown in Fig. 2, it being understood that the number of the grooves may be varied as needed to takecare of all the yarns that have to pass over the roller 3i.

The process and apparatus of the invention may be readily adapted for coloring some or all oi the warp yarns, for purposes of identification, decoration, and the like. For example, when it is desired to color some. but not all, of the warp yarns, a second size box in may be positioned in iront of the box I! as shown in Fig. 3. Yarns Ila are then led from a second beam Ila through 6 la and the other yarns to, all or the yarns Illa being passed through a common padder comprising the rolls 2 la and 22a.

The colored yarns are then passed by means and uncolored yarns come together and pass under the common roll 3. after which the yarns are treated collectively in the remaining boxes I! and I8.

It is to be understood that the sizing com position in the box I! may be colorless or colored a diflerent color than the sizing composition in the box i211. Since the colored yarns do not contaot each other until the size has been coagulated in the box i8, while the yarns are maintained separate from each other, there will be no bleeding of the colors from one set of yarns to another. After coagulation, the difierently colored yarns pass together side by side through the remaining treatments but there is no bleeding because the size has already been coagulated. It is to be understood that when dyestufls are employed for coloring the yarns, the leuco compound of the dye may be employed in the size boxes I2 or a and the developer for the dye may be incorporated in the box it in compatible admixture with the coagulating agent. Suitable dyestllfis which can be added to alkaline solution of ceilulosic colloids in a two-step treatment as just described are disclosed and claimed in my prior U. 8. Patent No. 2,259,196.

The present process and apparatus embody many advantages over prior and conventional means of slashing warp yarns. In the first place. the present invention provides means for treating a multiplicity of the yarns while arranged as a weftless web without permitting the yarns to stick together when sized because the yarns are separated in passing into the coagulating bath and preferably also while being sized. By this means, the yarns are individually impregnated and/or coated with the size and individually treated with coagulants and, if desired, individually washed, whereupon the nap fibres are laid, the twist stabilized and the yarns given a relatively smooth surface and suitably stiffened to facilitate weaving. Finally, means have been provided for the first time of coloring some or all of the warp yarns without having the color bleed upon the adjacent colored or diilerently colored yams.

n is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statement 01' the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim new and desire to secure by Letters Patent is:

1. In an apparatus for sizing warp yarns with a coagulable tacky composition, the combination of, means to treat a multiplicity of warp yarns with said tacky composition, a pair of pressure rollers for subjecting said yarns to pressure while the yarns are wet with said composition, a grooved roller positioned prior to and adjacent to said pressure rollers for leading the yarns in parallel 7' 1 separate relation' betwe en said pressure rollers, means to pass said yarns through a coagulant !or said composition. and means to maintain said yarns in a separated state while they are passing" through said coagulant.

- 2. In an apparatus for sizing warp yarns with a coagulable tacky composition, the combination g of, a plurality of vats adapted to' contain diflerent sizing compositions, means for passing some I ofthewarp yarn through one of said vats, means for. passing alternate .warp yarns through the other vat, a pair of pressure rollers for subjecting each of said sets of yarns to pressure whilewet with said composition, a grooved roller positioned prior to and adjacent said pressure rollers all of said yarns v 1 said compositions, and means to separate the f ferent sizing composition, separately subjecting both sets of yarns to pressure while said yarns are maintained in a separated state and passing all of said yarns through a common coagulant while maintaining said yams in a separated state while passing through said coagulant.

' JAMES ANDREW CLARK.

through a coagulant of 3. In a process for sizing warp yarns with .a 

